Work out crash force instantly with clear inputs, formula shown and shareable results.
Crash force is mass times deceleration, where deceleration is v squared over twice the crush distance. That is why crumple zones matter so much: extending the crush from 0.3 to 0.6 m halves the peak force on everything inside the car.
Crash force
a = v^2 / (2 x crush distance); F = m x a; KE = 0.5 m v^2
They extend the distance over which the car stops, and force is inversely proportional to that distance. Doubling the crush halves the force.
Restrained occupants routinely survive 20-30 g with modern belts and airbags. Above about 50-60 g survival becomes unlikely.